Automatic control for letoff mechanism of looms



Feb. 26, 1946. H, KURKJIAN 2,395,630

AUTOMATIC CONTROL FOR LET-OFF MECHANISM OF LOOMS Filed Sept. 28, 1943Patented F eb. 26, 1946 AUTOMATIC CONTROL FOR LETOFF MECHANISM OF LOOMSYervant H. Kurkjian, Clifton, N. J.

Application September 28, 1943, Serial No. 504,180

1 Claim.

This invention relates to an automatic control for let-ofi mechanism oflooms, and the like, and has for one of its objects the production of asimple and efiicient automatic let-01f control which will control thetension of the brake band of the warp beam in a proper manner tomaintain a uniform tension of the warp threads carried by the warp beam.

A further object of this invention is the production of a simple andefficient means for controlling the tension of the brake band of thewarp beam of a loom, wherein the control means i located below andextends longitudinally of the beam in one form illustrated.

Other objects and advantages of the present invention will appearthroughout the following specification and claim.

In the drawing- Figure 1 is a fragmentary front elevational view of theautomatic let-off control;

Figure 2 is a fragmentary sectional view taken on line 22 of Figure l;

Figure 3 is an end elevational view of a modified form of the invention.

By referring to the drawing, it will be seen that ID designates thesupporting frame upon which is mounted in any conventional way, aconventional warp-supporting beam II. The warp I2 is wound upon the beamII in the usual manner. A brake drum I3 is carried by the beam H, and abrake band I4 is anchored, as at l5, at one end to the frame It. Thebrake band I4 is secured at its opposite end, asat Hi, to the brakelever ll. The brake lever I1 is pivoted to the frame ||l by means of a,pivot l8, and carries, at its opposite end, a pivoted depending link l9,as shown in Figure This link I9 is pivotally connected to the inner end2|] of a weight or tension lever 2|, which lever 2| is pivotallysupported upon the frame I by a pivot 22.

A weight 23 is adjustably mounted in a selected position upon the weightlever 2|, and a spring-pressed contact roller 24 is carried by a bracket25, which is in turn pivotally carried, as at 26, upon the lever 2|. Thiroller 24 contacts with the warp l2 in the manner shown in Figures 1 and2, and is firmly held in this contacting position by means of the spring21. As the warp I2 is unwound from the beam II, the roller 24 will moveinwardly toward the beam II to the dotted line position shown in Figure1, thereby reducing the pressure upon the weight beam 2| and alsoreducing the tension of the brake band l4 upon the brake drum IS in amanner similar to that described in my application Serial Number477,743. As this tension is reduced, the brake band It will be looseneddue to the reduction of pressure upon the lever 2|. Consequently. as thewarp is unwound from the beam, the brake band Will be loosened so as tomaintain at all times a substantially uniform tension upon the warp. Thetension of the brake band M will be regulated in ratio to the unwindingof the warp, the

position of the roller 24 shifting automatically as the diameter of thewarp reduces.

In Figure 3, there is shown a modification of the invention, wherein thecontrol is mounted at the end of the frame It. The Warp supporting beamI l is carried above the frame Ill as shown. and the warp |2 is carriedby the beam II. A brake drum I3 is also carried by the beam II and abrake band m is secured at one end to the frame Ill, as at l5, and atits opposite end, as at I6 to the brake lever H Thi lever ll is pivotedto the frame NJ, as at l8, and supports at its inner end a pivoted linkIS. The link l9 is pivoted'to the inner end 2&1 of a tension lever 2|,the lever 2| being pivoted as at 22 to the frame Ill.

The tension lever 2| is connected at its outer end to a dependingtension spring 21 and the opposite end of the spring 21 is connected toa crank arm 26 of the warp-engaging bell crank lever 25 The lever 25carries a roller 24 which contacts the warp l2 wound upon the beam IIand as the warp is unwound the lever 25- will swing toward the warp inthe direction of the arrow and relieve the tension on the spring 21*,the lever Il the lever Il and the brake band 12 Consequently, thetension of the warp will, in this manner, be automatically keptsubstantially uniform at all times.

Having described the invention, what I claim is:

An automatic let-off control of the class described comprising asupport, a beam carried by the support, a warp. wound upon the beam, abrake drum carriedby the beam, a brake band passing over the drum, abrake lever mounted adjacent the drum, the brake band engaging one endof the brake lever, a pivot supporting the brake lever, a tension leverpivoted to said support, a link connecting the adjoining end of saidtension lever to the adjoining end of said brake lever, a dependingtension spring connected to the opposite end of the tension lever, abell crank warp-engaging lever pivoted to the frame, said warp-engaginglever having at one end a warp contacting means, and at its other end a.crank arm engaging said tension spring for maintaining asubstantiallyuniform tension upon the Warp at all times and forregulating the pull upon the brake band as said warp unwinds from thebeam.

